Utility and Safety of Transbronchial Biopsies Among Lung Transplant Recipients Admitted to the MICU

Abstract

PURPOSE: To study the utility and safety of bronchoscopy/transbronchial biopsies (TBBX) among lung transplant (LTx) recipients in MICU METHODS: We reviewed charts and studied indications, histopathology and safety of bronchoscopy/TBBX for LTx recipients in MICU between 1/1/2009 and 12/31/2011. Study was IRB approved. RESULTS: Eighteen patients underwent twenty bronchoscopy/TBBXs. Mean age (+/-SD) at transplant was 54.4+/-13.5 years. Bronchoscopy was performed 195+/-190 days post-transplant and 2.9+/-3.1 days after MICU admission. UIP/IPF and COPD were common transplant diagnoses. Ten patients received bilateral lung transplants. Hypoxemia was the most common reason for MICU admission. Transplant lung infiltrates were observed among all patients on imaging (CT/CXR). TBBX was mostly performed to differentiate between infection/acute cellular rejection (ACR). Mechanical ventilation was required during eighteen procedures. Diagnostic tissue to evaluate for ACR was not obtained during 5/18 procedures. Fifty-one diagnostic specimens were obtained after ninety-one passes. Fluoroscopy was used for 8 procedures. The most common histopathology was acute lung injury (ALI)/inflammation (n=14). Of the four ACRs, three were minimal (A1) and one was mild (A2). ALI was seen on three ACRs. All ACRs were observed within one year post-transplant. A2 rejection was treated with pulsed steroids, and A1 with augmented immunosuppression. C3D/C4D was negative for 12 and tissue non-diagnostic for 2 procedures. Concomitant TBBX and BAL were done among sixteen patients. ALI was seen among seven of eight patients who required directed antimicrobials for pathogenic microorganisms. These included bacteria (P.aeruginosa,MRSA), viruses (CMV,RSV) and fungi (A.fumigatus). Two patients had coexisting ACR. Complications resulting in aborted procedure included hypoxia (1), hypotension (1) and atrial fibrillation with rapid ventricular rate (2 in same patient). One patient (5%) had pneumothorax despite fluoroscopy guidance, requiring chest tube. CONCLUSIONS: TBBX diagnosed minimal/mild ACR (A1,A2), all within first year post-transplant ALI frequently associated with acute infection, found on BAL Complication rate high .